Novel Antitumor Sesquiterpenoids in Achillea millefolium

Achillea millefolium Linnaeus is used as an antipyretic and diaphoretic in cases of the common cold and as an emenagogue in Europe, U.S.A., and Asian Countries. Its use against cancer has also been reported. During our search for antitumor components in higher plants, the methanol extract of flowers of Achillea millefolium was found to exhibit activity against mouse P-388 leukemia cells in vivio. Bioassay-directed fractionation led to the isolation of three new sesquiterpenoids, achimillic acids A, B and C, as methyl esters. We report here the isolation, structural determination and antitumor activity of these compounds.